Add a page function for a framed vertex iterable. Remove some warnings
by parametising the Gremlin functions. Still much rationalisation
needed.
Break out the streaming page code into a separate function and make it protected
Add a REST endpoint for getting the history for an item.
Only add scopes to IDs if not the system scope
Add a BundleUtils class which contains some functions for doing
immutable get/set operations on the tree via the use of Xpath-like
paths such as 'describes[0]/identifier' (identifier node of
first 'describes' relation.)
Commonise some path-parsing logic into a couple of helper classes.
More developing of the bundle-munging tools.
Put the date period relation on the DocumentDescription node instead
of the document description. This is (I suppose) theoretically more
correct but comes at the expense of complicating things a great deal,
particularly the tests which do bundle munging. Also added is a short-
cut Gremlin method on the DocumentaryUnit to get all the associated
date periods.
Merge branch 'dates_periods_on_descriptions' of github.com:mikesname/neo4j-ehri-plugin into dates_periods_on_descriptions